diff --git a/src/quasifill.jl b/src/quasifill.jl
index e3ae193..e4b5f84 100644
--- a/src/quasifill.jl
+++ b/src/quasifill.jl
@@ -261,9 +261,9 @@ sum(x::AbstractQuasiFill) = getindex_value(x)*measure(axes(x,1))
 sum(x::QuasiZeros) = getindex_value(x)
 
 # define `sum(::Callable, ::AbstractQuasiFill)` to avoid method ambiguity errors on Julia 1.0
-sum(f, x::AbstractQuasiFill) = _sum(f, x)
-sum(f::Base.Callable, x::AbstractQuasiFill) = _sum(f, x)
-_sum(f, x::AbstractQuasiFill) = measure(x) * f(getindex_value(x))
+sum(f, x::AbstractQuasiFill) = _sum(f, x, :)
+sum(f::Base.Callable, x::AbstractQuasiFill) = _sum(f, x, :)
+_sum(f, x::AbstractQuasiFill, ::Colon) = measure(x) * f(getindex_value(x))
 
 
 #########
diff --git a/test/test_quasifill.jl b/test/test_quasifill.jl
index f50ad5f..30325c4 100644
--- a/test/test_quasifill.jl
+++ b/test/test_quasifill.jl
@@ -370,10 +370,12 @@ import QuasiArrays: AbstractQuasiFill
         @test zero(QuasiFill(0.5, ax, ax)) == QuasiZeros(ax,ax)
     end
 
-    @testset "maximum/minimum/svd/sort" begin
+    @testset "maximum/minimum/sort/sum" begin
         ax = [1,3,4]
         @test maximum(QuasiFill(1, ax)) == minimum(QuasiFill(1, ax)) == 1
         @test sort(QuasiOnes(ax)) == sort!(QuasiOnes(ax))
+        @test sum(QuasiFill(1, ax)) == sum(QuasiOnes(ax)) == 3
+        @test sum(exp, QuasiFill(0, ax)) == sum(exp, QuasiZeros(ax)) == 3
     end